From: Linus Walleij <linus.walleij@linaro.org>
To: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Cc: "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS"
<devicetree@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Bartosz Golaszewski <bgolaszewski@baylibre.com>,
Rob Herring <robh+dt@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Lee Jones <lee.jones@linaro.org>,
Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Subject: Re: [PATCH v4 5/5] gpio: syscon: Add support for the Xylon LogiCVC GPIOs
Date: Fri, 29 Nov 2019 10:24:58 +0100 [thread overview]
Message-ID: <CACRpkdaSLsq-oA7t8OL6_6L+ivZE+a83M4JbTZ2HW5E1E7c6yw@mail.gmail.com> (raw)
In-Reply-To: <20191128155438.325738-6-paul.kocialkowski@bootlin.com>
Hi Paul,
thanks for your patch!
On Thu, Nov 28, 2019 at 4:54 PM Paul Kocialkowski
<paul.kocialkowski@bootlin.com> wrote:
> The LogiCVC display hardware block comes with GPIO capabilities
> that must be exposed separately from the main driver (as GPIOs) for
> use with regulators and panels. A syscon is used to share the same
> regmap across the two drivers.
>
> Since the GPIO capabilities are pretty simple, add them to the syscon
> GPIO driver.
>
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
(...)
> +#define LOGICVC_CTRL_REG 0x40
> +#define LOGICVC_CTRL_GPIO_SHIFT 11
> +#define LOGICVC_CTRL_GPIO_BITS 5
> +
> +#define LOGICVC_POWER_CTRL_REG 0x78
> +#define LOGICVC_POWER_CTRL_GPIO_SHIFT 0
> +#define LOGICVC_POWER_CTRL_GPIO_BITS 4
> +
> +static void logicvc_gpio_offset(struct syscon_gpio_priv *priv,
> + unsigned offset, unsigned int *reg,
> + unsigned int *bit)
> +{
> + if (offset >= LOGICVC_CTRL_GPIO_BITS) {
> + *reg = LOGICVC_POWER_CTRL_REG;
> +
> + /* To the (virtual) power ctrl offset. */
> + offset -= LOGICVC_CTRL_GPIO_BITS;
> + /* To the actual bit offset in reg. */
> + offset += LOGICVC_POWER_CTRL_GPIO_SHIFT;
> + } else {
> + *reg = LOGICVC_CTRL_REG;
> +
> + /* To the actual bit offset in reg. */
> + offset += LOGICVC_CTRL_GPIO_SHIFT;
> + }
> +
> + *bit = BIT(offset);
> +}
The gpio-syscon.c is for simple syscons where the lines
you want to affect are nicely ordered in the registers.
It is intended to be generic.
This is kind of shoehorning a special case into the generic
code.
Isn't it more appropriate to create a specific driver for this
hardware?
Special get/set quirks for any possible quirky offset is
certainly not the way to go, if this should be supported
we need generic properties in struct syscon_gpio_data
to indicate the valid bits and offsets.
Yours,
Linus Walleij
next prev parent reply other threads:[~2019-11-29 9:25 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-28 15:54 [PATCH v4 0/5] LogiCVC mfd and GPIO support Paul Kocialkowski
2019-11-28 15:54 ` [PATCH v4 1/5] dt-bindings: Add Xylon vendor prefix Paul Kocialkowski
2019-11-28 15:54 ` [PATCH v4 2/5] dt-bindings: mfd: Document the Xylon LogiCVC multi-function device Paul Kocialkowski
2019-11-28 15:54 ` [PATCH v4 3/5] gpio: syscon: Add support for a custom get operation Paul Kocialkowski
2019-11-28 15:54 ` [PATCH v4 4/5] dt-bindings: gpio: Document the Xylon LogiCVC GPIO controller Paul Kocialkowski
2019-11-28 15:54 ` [PATCH v4 5/5] gpio: syscon: Add support for the Xylon LogiCVC GPIOs Paul Kocialkowski
2019-11-29 9:24 ` Linus Walleij [this message]
2019-12-03 8:57 ` Paul Kocialkowski
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CACRpkdaSLsq-oA7t8OL6_6L+ivZE+a83M4JbTZ2HW5E1E7c6yw@mail.gmail.com \
--to=linus.walleij@linaro.org \
--cc=bgolaszewski@baylibre.com \
--cc=devicetree@vger.kernel.org \
--cc=lee.jones@linaro.org \
--cc=linux-gpio@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=paul.kocialkowski@bootlin.com \
--cc=robh+dt@kernel.org \
--cc=thomas.petazzoni@bootlin.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).